But housing data has been an extremely powerful indicator of the economy’s health. Investors who pay attention to housing starts, historically, have had an early warning when the economy is about to sputter or even stumble into a recession.

Seven out of the past eight recessions since 1959 have come after housing starts fell by 30% or more, says Sam Stovall of S&P Capital IQ. The only time a recession didn’t occur following a 30% drop in housing starts was the one in the early 2000s following the bursting of the technology and telecom bubble. The indicator also failed in 1966, when housing starts fell 42% but no immediate recession occurred. The Standard & Poor’s 500 fell 22% in 1966, but the economy continued to expand until 1968.

Given the value of the housing indicator, investors have grown increasingly concerned about the health of housing. Housing starts jumped 42% in March 2013, but fell to 6% through March 2014. S&P Capital IQ is forecasting a 14% jump in housing starts for April, and investors are hoping that’s correct when the report is due out Friday.

USA TODAY markets reporter Matt Krantz answers a different reader question every weekday. To submit a question, e-mail Matt at mkrantz@usatoday.com or on Twitter @mattkrantz